<template>
    <div class="person">
      <h1>情况一：监视【ref】定义的【基本类型】数据</h1>
      <h2>当前求和为：{{sum}}</h2>
      <button @click="changeSum">点我sum+1</button>
    </div>
  </template>
  
  <script lang="ts" setup name="WatchDemo1">
    import {ref,watch} from 'vue'
    // 数据
    let sum = ref(0)
    // 方法
    function changeSum(){
      sum.value += 1
    }
    // 监视，情况一：监视【ref】定义的【基本类型】数据
    const stopWatch = watch(sum,(newValue,oldValue)=>{
      console.log('sum变化了',newValue,oldValue)
      if(newValue >= 10){
        stopWatch()
      }
    })
  </script>